return the end of week date using month and week number

create table test (yyyymm int, weekNum int)
Insert into test values(201402,6), (201401,1)

   select 
   --Dateadd(day, ((datepart(weekday,'1/1/2014')-7)+ weeknum*7)-1,
   Dateadd(day, ((datepart(weekday, dateadd(year, Datediff(year, 0, Cast(cast(yyyymm as varchar(6))+'01' as datetime)),0 ) )-7)+ weeknum*7)-1,
   Dateadd(year, datediff(year, 0, Cast(cast(yyyymm as varchar(6))+'01' as datetime)),0 )) 
   from test


   drop table test